What Are Examples of Lipids in Food? A Comprehensive Guide

December 21, 2025 •

3 min read

More than 95% of the lipids we consume in our diet are triglycerides, commonly known as fats and oils. These vital macronutrients are not only a concentrated source of energy but also play crucial roles in hormone production, vitamin absorption, and cell membrane structure. Understanding the different types of lipids and where to find them is key to a balanced diet.

Quick Summary

Lipids in food include fats, oils, phospholipids, and sterols found in both animal and plant products. Sources range from olive oil and avocados to dairy and fish, contributing to energy and vital bodily functions.

Key Points

Triglycerides are the most common lipid: Comprising over 95% of dietary lipids, they are found in both saturated forms (butter, meat) and unsaturated forms (oils, nuts).
Unsaturated fats are healthier options: Monounsaturated fats (like in olive oil and avocados) and polyunsaturated fats (like omega-3s in fatty fish) are linked to improved heart health.
Phospholipids build cell membranes: This type of lipid, found in eggs, soybeans, and peanuts, is crucial for maintaining the structure and function of all body cells.
Sterols are essential for hormones: Cholesterol, the most well-known sterol, is used by the body to synthesize hormones and vitamin D, and is found exclusively in animal products.
Trans fats should be avoided: Artificially produced trans fats, found in some processed foods and margarines, are particularly harmful to heart health and have been restricted in food production.
Lipids aid in vitamin absorption: Fat-soluble vitamins A, D, E, and K require lipids for proper digestion and absorption in the body.

What are lipids and their primary functions?

Lipids are a diverse group of organic molecules that are generally insoluble in water. Beyond simply being fats, this group includes oils, waxes, steroids, and phospholipids, each with unique roles in the body and in food. In our diet, lipids serve several essential functions:

Energy storage: Lipids are the body's most concentrated source of energy, providing 9 calories per gram, more than double that of carbohydrates or protein.
Hormone synthesis: Sterol lipids like cholesterol are precursors for essential hormones, including sex hormones and corticosteroids.
Vitamin absorption: Lipids transport and aid in the absorption of fat-soluble vitamins (A, D, E, and K).
Cell structure: Phospholipids are fundamental building blocks of cell membranes, providing a protective barrier.
Insulation and protection: Stored fat provides insulation to help regulate body temperature and cushions vital organs.

Main types of lipids and their food sources

Dietary lipids can be primarily categorized into three main groups: triglycerides, phospholipids, and sterols. Each type has a distinct chemical structure and is found in a variety of foods.

Triglycerides (Fats and Oils)

Triglycerides are the most common form of lipid in both food and the human body. They consist of a glycerol backbone attached to three fatty acid chains and are the main component of body fat and vegetable oils. Triglycerides are further broken down into two main sub-types based on their fatty acid saturation:

Saturated Fats: Fatty acid chains without double bonds, making them typically solid at room temperature.
- Animal sources: Fatty cuts of meat (bacon, beef), high-fat dairy products (butter, cheese, cream).
- Plant sources: Tropical oils such as coconut oil and palm oil.
Unsaturated Fats: Fatty acid chains with one or more double bonds, causing kinks that prevent tight packing and keep them liquid at room temperature.
- Monounsaturated Fats (MUFAs): One double bond. Found in olive oil, avocados, nuts (almonds, cashews), and seeds.
- Polyunsaturated Fats (PUFAs): More than one double bond. Sources include soybean oil, sunflower oil, walnuts, flaxseeds, and fatty fish (salmon, mackerel, sardines).

Phospholipids

Making up about 2% of dietary lipids, phospholipids are crucial for forming the protective membranes of all body cells. Their unique structure, with a water-loving head and water-repelling tails, allows them to act as emulsifiers in food, helping to mix fats and liquids.

Food sources rich in phospholipids:
- Egg yolks
- Soybeans (Lecithin is a common phospholipid food additive)
- Liver
- Peanuts
- Animal meat

Sterols

Sterols are a class of lipids with a distinct multi-ring structure. The most well-known sterol is cholesterol, which has an undeservedly notorious reputation. While our bodies produce most of the cholesterol they need, it is essential for synthesizing hormones and vitamin D.

Food sources containing cholesterol (found only in animal products):
- Eggs
- Meats (beef, poultry)
- Dairy products (cheese, milk)
- Shellfish (shrimp)

Comparison of dietary fat types

Understanding the differences between fat types is key to making informed dietary choices. While all lipids are essential, the American Heart Association recommends prioritizing unsaturated fats.


Feature	Saturated Fats	Monounsaturated Fats (MUFAs)	Polyunsaturated Fats (PUFAs)	Trans Fats
Appearance	Solid at room temperature	Liquid at room temperature	Liquid at room temperature	Semi-solid or solid
Primary Sources	Red meat, butter, cheese, coconut oil	Olive oil, avocados, most nuts	Fatty fish, flaxseeds, walnuts, soybean oil	Processed baked goods, shortening, some margarine
Double Bonds	No double bonds	One double bond	Two or more double bonds	Hydrogenated double bonds
Health Impact	Associated with increased LDL (bad) cholesterol levels	Can help lower LDL cholesterol and promote heart health	Essential fats like omega-3s are anti-inflammatory and beneficial for heart health	Raises LDL and lowers HDL (good) cholesterol, increasing heart disease risk

Conclusion: Making informed choices about lipids in food

Lipids are an essential part of any diet, serving as a concentrated energy source, aiding in vitamin absorption, and contributing to vital physiological functions. As a diverse group of compounds, they are found in a wide variety of foods, from the healthy unsaturated fats in olive oil, avocados, nuts, and fish to the saturated fats in dairy and meat. While moderation is key for all dietary components, consciously choosing healthier lipid sources, such as prioritizing unsaturated fats over saturated and avoiding trans fats, is important for long-term health. By understanding what are examples of lipids in food and their specific roles, you can make informed decisions to fuel your body and maintain overall wellness. For more details on the importance of lipid intake and heart health, visit Harvard's T.H. Chan School of Public Health website.

Frequently Asked Questions

The most common type of lipid found in food is triglycerides, which make up over 95% of dietary lipids and are what we commonly refer to as fats and oils.

No, not all lipids are bad. Healthy lipids like monounsaturated and polyunsaturated fats are essential for a balanced diet and offer significant health benefits, while unhealthy trans fats should be avoided.

Healthy unsaturated fats can be found in foods like olive oil, avocados, nuts (such as almonds and walnuts), seeds (flaxseeds, chia seeds), and fatty fish (salmon, sardines).

Saturated fats are typically found in animal products like butter, cheese, and red meat, as well as some tropical oils such as coconut oil and palm oil.

Phospholipids are present in egg yolks, soybeans, liver, peanuts, and various animal meats, and are often used as emulsifiers in food products.

The main difference is their state at room temperature. Fats are lipids that are solid at room temperature (like butter), while oils are lipids that are liquid at room temperature (like olive oil).

No, cholesterol is a type of sterol lipid found exclusively in animal products such as meat, dairy, and eggs. Plant-based foods do not contain dietary cholesterol.

Lipids provide a concentrated source of energy, aid in the absorption of fat-soluble vitamins (A, D, E, K), serve as building blocks for cell membranes, and are used to synthesize hormones.